Partially sprung drive, in particular for electric traction vehicles

ABSTRACT

A partially spring-loaded drive, particularly for electrically-powered rail vehicles, having a gear which, including an encapsulating gear housing, is seated on the wheel axle, and a pinion that is seated in the gear housing. The coupled motor is fixedly secured to the truck, and the resilient, elastic fastening of the gear housing to the truck is effected by way of at least two elastic spring elements that are mounted nearly vertically and diametrically opposite the pinion shaft, and whose lines of influence extend through the center of the pinion shaft. To avoid the disadvantages associated with truck-side pendulum suspensions of the drive housing outside of the pinion shaft, and provide a solution to the fastening of the gear housing to the truck, with which a stabilizing effect can be achieved for protecting the bearings in addition to an economical minimization of deformation losses of the coupling, a defined radial prestressing of the gear housing (3) with respect to the wheel set (4/5) is established using the transverse elasticity of the spring elements (6). The radial prestressing can usefully be established above and below the gear housing (3) by way of an arrangement of rubber thrust springs having support surfaces.

BACKGROUND OF THE INVENTION

The invention relates to a partially spring-mounted drive, particularlyfor electrically-powered rail vehicles, of the type having a gear which,including an encapsulating gear housing, is seated on the wheel axle,and a pinion that is seated in the gear housing, with the coupled motorbeing fixedly secured to the truck and the resilient, elastic fasteningof the gear housing to the truck being effected by at least two elasticspring elements that are mounted nearly vertically and diametricallyopposite the pinion shaft, and whose lines of influence extend throughthe center of the pinion shaft. A drive of this type is known from thedocument DE-A-91 16 159.

There are numerous embodiments of partially spring-mounted drives havinga transverse traction motor. In a drive according to DE-AS 12 14 263,the gear, including an encapsulating gear housing, is seated on thewheel axle, and the motor pinion or pinion is seated in the gearhousing. In this instance, the motor is fixedly secured to the truck,and the gear housing is movably secured. On the one hand, apendulum-motion suspension is effected via a connecting rod and, on theother hand, a resilient, elastic support against the truck is effectedby way of two elastic spring elements that are mounted nearly verticallyand diametrically (central-symmetrically) opposite the pinion shaft, andwhose lines of influence extend through the center of the pinion shaft.A coupling is also typically disposed between the motor and the motorpinion or pinion.

The document mentioned at the outset, DE-A-91 16 159, discloses an axledrive, particularly for a rail vehicle wheel-set axle disposed in atruck, in which the axle of the drive motor extends parallel to thewheel-set axle, and the motor, which drives the wheel-set axle by way ofa spur gear that is fixedly connected to the wheel-set axle, also drivesa universal coupling and is fixedly connected to the truck. Thewheel-set axle is resiliently connected to the truck in such a way thatthe spring path is larger by a multiple in the one, direction that is,the vertical direction, than in the other, direction that is, thehorizontal direction. The spur gear is supported opposite the truck bymeans of a torque-converter bearing provided with universal joints. Theaxis of the torque-converter bearing intersects the axis of the driveshaft of the spur gear approximately perpendicularly, or passes close byit and extends in the direction of the largest spring path of thewheel-set axle. Thus, a fixing resilience of the universal joints at theends of the torque-converter bearing is provided that permits, aboveall, a resilience in the vertical direction, while the transverseresilience permits only a very limited horizontal flexibility for thepurpose of fixing the torque-converter bearing.

These constructions have system-stipulated disadvantages. With theincrease in driving speeds and motor rpms over time in the quest formore lightweight construction, the motor bearings can be reduced indesirable fashion, but the gear bearings must retain their size due tothe predetermined axle loads, or even be enlarged because of larger axlediameters. Because of high rpms in the event of a drive power outage,these bearings are in great danger because a stabilizing radial load isno longer present on account of the small gear mass that is to beprovided for the high-speed range.

It is the object of the invention to remedy this situation and provide asimple fastening of the gear housing to the truck with which astabilizing effect can be attained for protecting the bearings, inaddition to an economical minimization of the deformation losses of thecoupling.

SUMMARY OF THE INVENTION

The above object generally is accomplished according to the presentinvention by providing a spring loaded drive of the type initiallydescribed above with a defined radial prestressing of the gear housingwith respect to the wheel set with the prestressing being established bythe transverse elasticity of the spring elements.

Advantageous embodiments and modifications likewise are disclosed.

The invention is described in detail below by way of an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view of a drive having a motor and a wheel set, and

FIG. 2 is a sectional view along the sectional plane A-A in FIG. 1 (viewdoes not include wheel set).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows the complete drive for a wheel set having a motor 1, which,via a coupling 2, drives a pinion, not visible, that is encapsulated ina gear housing 3. The pinion meshes with a gear, not visible, that isconnected to a traction wheel 4 of the wheel set in the gear housing 3,which itself is seated on the wheel-set axle 5. The motor 1 is fixedlyanchored in the truck. The gear housing 3 is closed by a oil pan 9having a viewing glass 10 and a waste-oil screw 11.

As can be seen particularly in the sectional view of FIG. 2--in whichmotor 1 and wheel set 4, 5 are omitted--the gear housing 3 is supportedabove and below against the truck 7 by way of two elastic springelements 6 that are mounted vertically and diametrically opposite thepinion shaft 8, and the lines of influence of the spring elements 6, inthis case rubber transverse springs, extend through the center of thepinion shaft 8. This results in a resilient, elastic fastening of thegear housing 3 with an imaginary inner system point of rotation thatpasses partly through the center line of the pinion shaft 8. Springdeflections of the wheel-set axle remain practically without effect onthe pinion shaft 8, significantly reducing coupling wear. A definedprestressing of the gear housing 3 with respect to the wheel set 4/5 isestablished by a transverse elasticity of the spring elements 6. As aresult, the bearings of the gear housing 3 on the wheel axle 5 retainthe necessary minimum stress, even during no-load operation.

I claim:
 1. A partially spring-loaded drive for electrically-poweredrail vehicles, with said drive having a gear which, including anencapsulating gear housing, is mounted on a wheel axle, and a pinionthat is mounted in the gear housing, and is coupled via a pinion shaftto a drive motor fixedly secured to a trucks and a resilient, elasticfastening of the gear housing to the truck effected by at least twoelastic spring elements that are mounted nearly vertically anddiametrically opposite the pinion shaft, and whose lines of influenceextend through the center of the pinion shaft, and wherein thetransverse elasticity of the springs is such that a desired defined andadjusted radial prestressing of the gear housing with respect to therespective wheel axle and attached wheels is provided.
 2. A partiallyspring-loaded drive according to claim 1, wherein the radialprestressing is established above and below the gear housing by anarrangement of said elastic spring elements in the form of rubbertransverse springs having support surfaces engaging the gear housing.